1. Field of the Invention
The invention relates in general to a color filter and manufacturing method thereof, and more particularly to a color filter using optical proximity correction (OPC) technology and manufacturing method thereof.
2. Description of the Related Art
With the features of light weight, low power consumption and small volume, liquid crystal display (LCD) has gradually replaced CRT display and is now widely applied in electronic devices such as a notebook computer, personal digital assistant (PDA), mobile phone and liquid crystal TV. The design of color filter, an essential part to an LCD, greatly affects the quality and efficiency of the LCD.
Referring to FIG. 1A, a top view of the structure of a conventional delta-type color filter is shown. The color filter 100 comprises a number of red filtering units 110, a number of green filtering units 120 and a number of blue filtering units 130. Any three adjacent filtering units 110, 120 and 130 are arranged in a triangle as shown in dotted triangles in FIG. 1A. Furthermore, the adjacent filtering units 110, 120 and 130 are arranged in an equal interval d. In actual manufacturing process, three different masks are used to sequentially form a red filtering unit 110, a green filtering unit 120 and a blue filtering unit 130 by lithography. Generally speaking, the filtering units 110, 120 and 130 are over-lapped (d≈0), and uneven surface easily occurs to the color filter 100 on the junctions of the filtering units 110, 120 and 130 as shown in FIG. 1B. The unevenness affects the characteristics of subsequent liquid crystal package.
When the interval d between the filtering units 110, 120 and 130 gradually increases to between 0.2 μm and 0.3 μm, the surface of the color filter 100 can have a best flatness. However, dimples occur at the corners of the filtering units 110, 120 and 130 as shown in the doffed circles in FIG. 1C. The dimples would cause abnormal liquid crystal arrangement in subsequent liquid crystal package, leading to “light leakage” during the operation of the LCD and largely affecting the quality and the efficiency of the LCD.